Consciousness & Sleep Today’s Goal: Define the levels of consciousness and the stages of the sleep cycle.

Consciousness Awareness of ourselves & environmentAwareness of ourselves & environment PreconsciousPreconscious NonconsciousNonconscious UnconsciousUnconscious Dual processingDual processing

Circadian Rhythm Biological clock – regular bodily rhythms of 24-hour cycleBiological clock – regular bodily rhythms of 24-hour cycle Suprachiasmatic nucleus (SCN) – regulates gland production of melatoninSuprachiasmatic nucleus (SCN) – regulates gland production of melatonin

Sleep Cycle/Stages EEG – brain wave activityEEG – brain wave activity Stages 1-4 = NREM sleepStages 1-4 = NREM sleep REM sleepREM sleep

Electrooculograms – eye movementElectrooculograms – eye movement Electromyograms – muscle tensionElectromyograms – muscle tension

Today’s Goal: Define the levels of consciousness and the stages of the sleep cycle.Today’s Goal: Define the levels of consciousness and the stages of the sleep cycle.

NREM/REM Sleep NREM (non-rapid-eye-movement)NREM (non-rapid-eye-movement) –75% of sleep –Restores the body REM (rapid-eye-movementREM (rapid-eye-movement –25% of sleep –Restores brain –Vivid dreams –Body immobile

Awake & alert – Beta wavesAwake & alert – Beta waves –Faster, irregular waves –15-45 peaks per second Awake but relaxed – Alpha wavesAwake but relaxed – Alpha waves –Smooth, regular waves –10 peaks per sec.

NREM Stage 1 Theta wavesTheta waves ~10 min.~10 min. Transition from wakefulness to sleepTransition from wakefulness to sleep Hypnagogic state – brief dreamlike experienceHypnagogic state – brief dreamlike experience Hypnic jerks (body shutting down)Hypnic jerks (body shutting down)

NREM Stage 2 Theta wavesTheta waves Sleep spindles – brief bursts in wave frequencySleep spindles – brief bursts in wave frequency K Complexes – brief bursts in wave amplitudeK Complexes – brief bursts in wave amplitude

Stages 3 & 4 Delta wavesDelta waves ~30-40 min. of cycle Blood pressure dropsBlood pressure drops Slowed breathingSlowed breathing Tissue growth, repairsTissue growth, repairs Growth hormoneGrowth hormone

REM Sleep Paradoxical sleepParadoxical sleep Brain is active but body is immobileBrain is active but body is immobile Vivid dreamsVivid dreams Cortisol dropsCortisol drops Helps immune systemHelps immune system

Sleep Cycle